1. Field of the Invention
This invention relates to a fuel composition comprising a fuel with a gasoline-boiling point range and a vegetable oil containing 1,8-cineole as a major component, which has an improved octane number with less toxicity and which produces, after combustion, an exhaust containing carbon monoxide only in a slight concentration.
2. Description of the Prior Art
With the coming exhaustion of resources, it has been a recent increasing tendency to search for energy carrier capable of being used as a substitute energy. In particular, a liquid fuel capable of taking the place of petroleum has been desired as a fuel for internal combustion engine. However, in consideration of anti-knock performance, output power, fuel consumption per hour, toxicity, and poisonous ingredients in a combustion exhaust, fuels capable of taking the place of petroleum are difficult to find out.
As a fuel for automobiles, anti-knock performance is of a particular importance, and a fuel with a high octane number is required. Tetraethyllead has so far been popularly used for improving the anti-knock performance (or improving octane number). However, the use thereof is being restricted due to its toxicity and, after combustion, problem of causing atmospheric pollution.
It has been a recent practice to incorporate benzene, toluene, xylene, etc. in gasoline for improving the octane number, but these additives are also obtained from finite and exhausting fossil fuel such as petroleum or coal and are therefore restricted by the shortage of resources.
Further, from the point of view of poisonous ingredients contained in an exhaust, an exhaust of conventional gasoline contains carbon monoxide at such a high level in addition to the above-described lead compound that atmospheric pollution due to carbon monoxide has become a serious environmental problem.
As a result of various practical investigations to solve these problems, the inventors have found that a vegetable oil containing 1,8-cineole as a major component, when used as a fuel for internal combustion engine, surprisingly shows itself a high octane number, produces a high output power, and shows a low fuel consumption. Further, it has been found that the octane number of a fuel can be improved, without the addition of tetraethyllead or the like, by adding the vegetable oil to a fuel having a gasoline-boiling point range as an octane number improver and/or a fuel to prepare a fuel composition which exhibits the same performance as ordinarily used gasoline and which reduces the amount of carbon monoxide in a combustion exhaust. Thus, the present invention was achieved.